FILE - In this Aug. 27, 2008, file photo, former President Bill Clinton speaks at the Democratic National Convention in Denver. The way Democrats and Republicans treat their ex-presidents at convention time reflects each man's personal popularity and also how well he's weathered changes in party politics. It helps to be a dynamite speaker, too. Clinton scores on all three: his speeches are rousing, if long; his popularity extends to coveted independent voters; and his centrist appeal plays well across today's Democratic Party. It's no wonder that Democrats are have forgiven, if not forgotten, that business about Monica Lewinsky and impeachment that seemed to have permanently marred his presidency as it ended a dozen years ago. (AP Photo/Charlie Neibergall, File)

ADEL, Iowa (AP) — Republican vice presidential nominee Paul Ryan heaped praise on Bill Clinton Wednesday, holding him up as a model of reform and Barack Obama as his opposite just hours before the former president's speech to the Democratic National Convention.

Campaigning in Iowa, Ryan lauded Clinton administration action on welfare reform and spending reductions — areas where the GOP ticket has aimed some of its sharpest critiques of Obama, the incumbent Democrat.

Clinton, once an Obama critic, has become one of his biggest assets as the president scraps with GOP nominee Mitt Romney for re-election. Clinton, whose two terms ended on an economic high note, appears in a television ad where he likens Obama's agenda to his own.

Void of a single reference to Clinton-era scandals, Ryan's praise was a way to paint Obama as a failure on the GOP ticket's terms.

"Under President Clinton we got welfare reform," Ryan told an audience outside a small-town courthouse west of Des Moines. "President Obama is rolling back welfare reform. President Clinton worked with Republicans in Congress to have a budget agreement to cut spending. President Obama, a gusher of new spending."

Ryan, a House member from Wisconsin, also said a Clinton administration commission to study the future of Medicare inspired the GOP ticket's proposal to offer seniors a choice of traditional Medicare or a fixed government payment that could be used to buy private coverage.

"It's an idea that came out of the Clinton commission to save Medicare," Ryan said.

Ryan reminded the audience of supporters that the national debt surpassed $16 trillion this week on the first day of the Democratic convention in Charlotte, N.C.

"That's a country in decline," Ryan said.

Among Ryan's criticisms was an indirect reference to the GOP ticket's debunked claim that Obama has waived the work requirement on Clinton-era welfare reform.

Ryan also neglected to mention that the Clinton action he praised came after Democrats lost control of the House and Senate in 1994, having raised taxes in 1993 and tried unsuccessfully to enact a national health care program the following year.

The balanced budget agreement Clinton made with then-House Speaker Newt Gingrich, a Georgia Republican, created the first new benefit program in years, a health insurance program for low-income children not eligible for Medicaid.

And Ryan made no mention of the scandals that marked the Clinton administration. Most notably the GOP-controlled House approved four articles of impeachment in 1998, though the Senate voted against removing Clinton from office.

Ryan was elected in 1998, but the impeachment votes took place before Ryan assumed his seat.

By treading lightly on the former president, Romney's team also is making a play for Clinton supporters who are disappointed by Obama.

Romney's campaign has stepped up its effort to appeal to working-class white voters in pivotal states such as Florida, Iowa, Ohio and Virginia.

White voters without college degrees preferred Clinton's wife, Hillary, over Obama in states such as Ohio during the 2008 Democratic presidential nominating campaign. They now prefer Romney over Obama by more than 20 percentage points, according to an Associated Press-GfK poll published last month.

Clinton's prime time speaking slot at the convention, like his central role in the Obama ad airing in key states, is seen as an effort to narrow Romney's advantage with these voters, who could tip the balance in a close election.

"Bill Clinton has very favorable approval numbers," said Katon Dawson, a national political consultant and former South Carolina Republican Party chairman. "He's a pretty tough adversary for us."